1. Field of the Invention
The present invention relates to a printed circuit board and a printed circuit board base material for use in the printed circuit board.
2. Description of the Prior Art
On conventional printed circuit boards, circuit layers are formed on a printed circuit board base material comprising glass cloth impregnated with an epoxy resin, through holes are provided for connecting the circuit layers.
When electronic parts are mounted on such printed circuit boards, however, the coefficient of thermal expansion of the printed circuit board base material is larger than the coefficient of thermal expansion of the electronic parts, so that the thermal expansion of the printed circuit board base material is larger than the thermal expansion of the electronic parts, which may sometimes damage the electronic parts. Furthermore, the specific gravity of the printed circuit board base material is so large that the printed circuit board weighs more.